1) I profoundly dislike the 'feature' in Unity that requires you to look at a directory window in either 'Places' or 'Tree' mode, neither which is fully functional. They should be combined, but if that is impossible, at least their toggle should be on the pop-up context menu, not by an obligatory trip to the menu bar. I also wonder why the 'List/Compact List/Icon' toggle can't be on the context menu.
Xubuntu's Thunar file manager is much more well-behaved, although it does have an annoying bug that expands the 'File System' listing when any platter is selected. I heard this will be fixed in the next release.
One thing I like in Thunar is batch file rename: select multiple files. Many character substitution modes are then available to let you rename them all with one action. You can even change tags in image and music files. This does not exist in Unity, AFAIK.
2) The network manager is an embarrassment. It takes too long to lock in, and on some computers, you have to disable networking, go into suspend, then come out of suspend and enable networking again to get a signal. My current phone (HTC One -V with Android) and a 2002 iBook both acquire wifi almost instantly.